Receptors for 5-hydroxytryptamine (5-HT) are currently classified as 5-HT.sub.1 -like, 5-HT.sub.2 and 5-HT.sub.3. The 5-HT.sub.1 -like class has been further subdivided into 5-HT.sub.1A, 5-HT.sub.1B, 5-HT.sub.1C and 5-HT.sub.1D subtypes. The compound 5-HT has the formula: ##STR2##
Evaluation of the receptor binding profile of sumatriptan, a potential drug for the acute treatment of migraine, strongly suggests that its stimulation of the 5-HT.sub.1D receptor subtype is relevant to the reported antimigraine effects. Sumatriptan is an indole of the formula: ##STR3## Further compounds to bind the 5-HT.sub.1D receptor as well as other 5-HT receptors are of interest to improve migraine treatment.